Tyrosinaemia type I is a genetic, metabolic condition in which the body is unable to properly break down tyrosine due to genetic changes (variants) in the FAH gene. Tyrosine is an amino acid that is a building block for many proteins.¹ The FAH gene produces an enzyme called fumarylacetoacetate hydrolase (FAH), which is involved in the final step of breaking down tyrosine.^2,3 The breakdown of tyrosine is a multistep process. In tyrosinaemia type I, there is low or no FAH activity, resulting in a build up of tyrosine metabolites that can cause damage to the liver, kidney and central nervous system. This can lead to serious complications if untreated.⁴

In Australia, as of April 2026, tyrosinaemia type I is now often detected shortly after birth via newborn bloodspot screening (NBS) programs. Additional testing is required to confirm the diagnosis. For individuals who are not or were not screened at birth, tyrosinaemia type I is often diagnosed after symptoms develop. Early diagnosis and prompt treatment of tyrosinaemia type I can help prevent or reduce the risk of life-threatening complications.

There are also two other types of tyrosinaemia (tyrosinaemia type II and tyrosinaemia type III) that are caused by genetic changes in other genes and are currently being detected via the newborn bloodspot screening (NBS) programs.

Synonyms: hereditary tyrosinaemia (type 1); HT1; fah deficiency; fumarylacetoacetase deficiency; fumarylacetoacetate hydrolase deficiency; hepatorenal tyrosinemia; type I tyrosinemia^2,5

Universal rare disease classifications provide a common language for recording, reporting and monitoring diseases. Please visit the Rare Disease Classifications page for more information about these internationally recognised classifications.

ORPHA:882 Tyrosinemia type 1

ICD-11: 5C50.11 Tyrosinaemia type 1

Symptoms can present within the first few months of life (acute form) or later (chronic form). The acute form is more common and severe than the chronic form.²

The symptoms of tyrosinaemia type 1 may include failure to thrive (not gaining weight and growing at expected rate), vomiting, diarrhea, tendency to bleed easily, jaundice, enlarged liver (hepatomegaly), rickets (softening and weakening of bones in children).^1-5 Some infants may have a particular cabbage-like odor. Some children also may have what is called a neurologic crisis, which may include change in mental state, pain in the abdomen area (abdominal pain), reduced sensation in arms and legs (peripheral neuropathy) and respiratory failure.⁴ If left untreated, tyrosinemia type I can lead to life-threatening complications such as liver and kidney failure and for the acute form, this can progress quite quickly.

Please speak to your medical team to learn more about the symptoms and complications of this condition.

Rare diseases are often serious and progressive, exhibiting a high degree of symptom complexity, leading to significant disability. Majority of the estimated two million Australians living with a rare disease meet the Australian Government’s definition for disability (in accordance to the Australian Public Service Commission and Australian Bureau of Statistics), and many experience severe and permanent disability impacts. If you or someone you care for is experiencing disability-related impacts from a rare condition, please speak with a health or disability professional for advice. Information about relevant disability support can be found at the RARE Portal’s Disability Support Information page.

Tyrosinaemia type I is a genetic condition. It is caused by disease-causing genetic changes (variants) in the FAH gene located on Chromosome 15.⁴

All individuals have two copies (alleles) of the FAH gene – one on each chromosome that is inherited from each parent. Tyrosinaemia type I is an autosomal recessive condition, which means both copies of the FAH gene must have the disease-causing genetic variants. More information on autosomal recessive inheritance pattern can be found at Centre for Genetics Education: Autosomal recessive inheritance.

If you would like to learn more about the inheritance and impact of this condition, please ask your doctor for a referral to a genetic counsellor. Genetic counsellors are qualified allied health professionals who can provide information and support regarding genetic conditions and testing. More information about genetic counselling can be found at:

• Information on Genetic Services
• The National and State Services pages underneath the ‘Genetic Counselling’ sections listed

Newborn screening

In Australia, tyrosinaemia type I is usually detected via the newborn bloodspot screening (NBS) programs.  Shortly after birth and with parental consent, a nurse or midwife will collect the baby’s blood via a heel prick blood test. The healthcare provider will then send it to a specific laboratory to test for a range of rare conditions, including tyrosinaemia type I. If the results of these tests suggest that the baby is at risk of having one of these conditions, laboratory staff will quickly get in touch with healthcare providers. The healthcare providers will then arrange for the baby to have further testing that will confirm whether the baby does indeed have the condition. The healthcare providers will also organise for the baby to receive urgent care if required. Depending on your state or territory, parents may or may not receive a notification if the test results are clear. You can find out more about NBS in your state or territory at Australian Government Department of Health, Disability and Ageing: Delivering newborn bloodspot screening programs. 

Newborn bloodspot screening is a reliable way to check for certain rare conditions early in life. Although it’s extremely rare, cases can sometimes be missed. If you are concerned your baby may have a condition that they have already been screened for, you should contact a medical professional.  

As of April 2026, tyrosinaemia type I has been implemented in Australia’s newborn bloodspot screening (NBS) programs in every state and territory. Babies that were born prior to that may not have been screened for tyrosinaemia type I.

Diagnosis

A diagnosis of tyrosinaemia type I may be suspected based on an abnormal result from NBS but additional tests and a clinical examination will be required to confirm a diagnosis. For individuals who are not screened at birth, tyrosinaemia type I is often diagnosed after symptoms develop. 

Diagnosis of tyrosinaemia type I may be made based on clinical examination, laboratory tests on blood and urine samples to look for tyrosine metabolites such as succinylacetone, and genetic testing.²

As part of the diagnostic process, doctors may do a differential diagnosis, which is to rule out other conditions that have similar symptoms, such as classic galactosemia, hereditary fructose intolerance, fructose 1,6 diphosphatase deficiency, Wilson’s disease and certain mitochondrial disorders.⁴

Please speak to your medical team to learn more about the available pathways for diagnosis of this condition.

There is currently no curative treatment for tyrosinaemia type I. Treatment of tyrosinaemia type I is aimed at stopping the build-up of the toxic metabolites and management of complications.

In Australia, there is currently one approved treatment that is subsidised by the Life Saving Drugs Program (LSDP) for eligible patients with a confirmed diagnosis of tyrosinaemia type I. More information about eligibility requirements for this treatment can be found at Australian Government Department of Health, Disability and Ageing: Hereditary tyrosinaemia (type 1) – Guidelines.

Individuals with tyrosinaemia type I will also need to go on a low protein diet (to restrict intake of tyrosine and phenylalanine), together with a specialised nutritional supplement.  The ASIEM Low Protein Handbook for Tyrosinaemia has information about the special diet required for tyrosinaemia type I. The tolerated amount of protein in diets may vary between individuals and may change over time.⁶ It should be managed by a metabolic specialist team.

Strategies may be taken to manage symptoms and complications, such as monitoring and management of liver disease as well as management of hypertension, osteoporosis and rickets.⁴

Please speak to your medical team to learn more about the possible treatment or management options for your condition. Treatment will depend on an individual’s specific condition and symptoms. It is also important to stay connected to your medical team so that you can be made aware of any upcoming clinical trial opportunities. For many rare diseases, treatment options may be limited. Participation in a clinical trial may provide access to new or emerging therapies.

Healthcare professionals involved in the care of individuals living with tyrosinaemia type I may include general practitioners (GP), paediatricians, metabolic physicians, metabolic nurses, gastroenterologists, nephrologists, neurologists, oncologists and others. The need for different healthcare professionals may change over a person’s lifetime and extend beyond those listed here.

Clinical care for rare diseases often involves a multidisciplinary team of medical, care and support professionals. Please note that the information provided here is as a guide and that RVA does not necessarily monitor or endorse specific clinics or health experts.

This may not be applicable to all rare diseases but for many, palliative care services may be relevant and useful. Palliative care services are available for people (adults, children and their families) living with a life-limiting illness and is not only for end-of-life care. It can also help at any stage of illness from diagnosis onwards, and will look different for different people. Palliative care services provide assistance, support, resources and tools to help people manage their illness and the symptoms, ease pain, and improve comfort and quality of life. If this is relevant to you and you wish to find out more information about palliative care and how it can help you, please visit:

• Australian Institute of Health and Welfare: Palliative care Overview
• Australian Government Department of Health, Disability and Ageing: Palliative care
• Palliative Care Australia

The ASIEM Low Protein Handbook for Tyrosinaemia has been prepared by members of the
Australasian Society for Inborn Errors of Metabolism (ASIEM), a special interest
group of the Human Genetics Society of Australasia (HGSA), and published in 2007. This handbook contains information relevant to the management of Tyrosinaemia type 1.⁶

The following guidance is available from international experts outside Australia; however, there may be information that is not relevant or applicable to the Australian context, and may not be up to date:

Recommendations for the management of tyrosinaemia type 1 – developed by medical experts with experience managing Tyrosinaemia type 1 from six different countries; published in 2013.

Individuals living with rare diseases may have complex medical issues and disabilities, which are not always visible. It is often useful to refer to their medical history as well as personal information such as a medical card, doctor’s letter, or if available, a rare disease passport, for relevant information.

In addition, individuals, their parents, families and carers often develop extensive expertise on their specific rare disease. It is important to recognise that they can contribute valuable knowledge about their rare condition. Rare diseases often impact individuals differently, so it’s important to consider a person’s lived experience.

If you know of any relevant emergency management guidelines or information relevant to emergency care, please let us know via the  Contribute page.

Metabolic Dietary Disorders Association (MDDA): Latest Research Updates has information about key areas of ongoing research for various inborn errors of metabolism conditions, including amino acid disorders.

There are specific considerations around participating in rare disease research, including clinical trials. It is important to be mindful of issues such as data privacy, research ethics, consent and differences in research regulations between Australia and other countries. For more information, please visit the RARE Portal’s Considerations for Participating in Health and Medical Research page.

If you are interested in finding clinical trials for your condition, please visit the following websites; however, there may not be any clinical trials available:

• Australian Clinical Trials
• ClinicalTrials.gov

It is best to discuss your interest in research, including clinical trials,  with your medical team to determine suitability and eligibility.

Australian Organisation:

Metabolic Dietary Disorders Association (MDDA)
Website: https://mdda.org.au/

Metabolic Dietary Disorders Association Inc (MDDA) is the national peak consumer body dedicated to supporting, educating, connecting, and representing all individuals their families and carers living with Inborn Errors of protein Metabolism (IEpM).

Please note that RVA does not monitor or endorse each group/organisation’s operational governance and activities. When engaging with a group, please consider the information on the RARE Portal’s Finding Helpful Peer and Community Supports page.

Tyrosinaemia type I varies between individuals, and each person’s experience is unique.

If you would like to share your personal story with RVA, please visit the Rare Voices Australia: Share Your Story page. RVA will consider your story for publishing on our website and inclusion on the RARE Portal.

The ASIEM Low Protein Handbook for Tyrosinaemia

For information on available government and social services that provide support for individuals with a rare disease, please visit the National and State Services pages.

People living with a rare disease often face unique challenges such as diagnostic delays, misdiagnoses, limited treatment options, and limited access to rare disease specialists and support. These challenges may impact people’s emotional wellbeing and quality of life. Many find it helpful to seek mental health and wellbeing support to cope with ongoing stress and uncertainty. Connecting with people who have shared experiences through a support group may also be helpful. Information about relevant mental health and wellbeing support can be found at:

• Mental Health and Wellbeing Support for Australians Living with a Rare Disease
• The National and State Services pages underneath the ‘Mental Health’ sections listed

Further information on tyrosinaemia type I can be found at:

• The ASIEM Low Protein Handbook for Tyrosinaemia
• Genetic and Rare Diseases (GARD) Information Center: Tyrosinemia type i
• National Organization for Rare Disorders (NORD): Tyrosinemia Type 1

Orphanet: Tyrosinemia type 1

GeneReviews^®: Tyrosinemia Type I

Online Mendelian Inheritance in Man, OMIM^®: #276700 Tyrosinemia, Type 1; TYRSN1

This page has been developed by Rare Voices Australia (RVA)’s RARE Portal team. If you would like to see more information added to this page, please reach out via the Contact form. If you would like to share relevant resources for this condition, please visit the Contribute page.

If you are aware of any additional information that may benefit stakeholders with an interest in this page, or if you notice any broken links or inaccurate information, please let us know via the Contribute page.